why datepicker(field:yyrq) display "1900-01-01"

dhx.ready(function(){
dhx.ui({
view:“popup”,
id:“sgry_popup”,
body:{
view:“list”,
id:“sgry_list”,
datatype:“json”,
select:true
}
}).hide();

dhx.ui({
	view:"popup",
	id:"shdd_popup",
	body:{
		view:"list",
		id:"shdd_list",
		datatype:"json",
		select:true
	}
}).hide();
var config = {
	type:"wide", rows:[
		{view:"form", id:"myform", width:1018, height:170, elements:[
			{type:"clean", rows:[
				{type:"clean", cols:[
					{view[b]:"datepicker[/b]", id:"yyrq", label:"yyrq", labelWidth:80, weekHeader:true, startOnMonday:false},
					{view:"richselect", id:"yygp", label:"yygl", labelWidth:80, datatype:"json", url:"get_gpzd_json.asp"},
					{view:"text", id:"yyzl", label:"yyzl", labelWidth:80},
					{view:"text", id:"sgry", label:"sgry", labelWidth:80, popup:"sgry_popup", readonly:true}
				]},
				{type:"clean", cols:[
					{view:"text", id:"gpyq", label:"gpyq", labelWidth:80, width:512},
					{view:"richselect", id:"fhdd", label:"fhdd", labelWidth:80, datatype:"json", url:"get_fhdd_json.asp"},
					{view:"text", id:"shdd", label:"shdd", labelWidth:80, popup:"shdd_popup", readonly:true},
				]},
				{type:"clean", cols:[
					{view:"text", id:"cphm", label:"cphm", labelWidth:80},
					{view:"text", id:"sjdh", label:"sjdh", labelWidth:80},
					{view:"text", id:"qbyf", label:"qbyf", labelWidth:80}
				]},
				{type:"clean", cols:[
					{view:"button", type:"form", id:"save", label:"save", inputWidth:150, align:"center", click:"save"},
					{view:"button", type:"form", id:"remove", label:"remove", inputWidth:150, align:"center", click:"remove"},
					{view:"button", type:"form", id:"reset", label:"reset", inputWidth:150, align:"center", click:"reset"}
				]}
			]}
		],
		rules:{
			yyrq:dhx.rules.isNotEmpty,
			yygp:dhx.rules.isNotEmpty,
			yyzl:dhx.rules.isNumber,
			sgry:dhx.rules.isNotEmpty
		}},
		{view:"grid", id:"mygrid", width:1018, scroll:"y", header:true, sorting:false, select:true, datatype:"json",
			fields:[
				{id:"sn", label:"sn", width:48, align:"center", template:"#sn#"},
				{id:"yyrq", label:"yyrq", width:100, align:"center", template:"#yyrq#"},
				{id:"yygp", label:"yygp", width:80, align:"center", template:"#yygp#"},
				{id:"yyzl", label:"yyzl", width:80, align:"right", template:"#yyzl#"},
				{id:"sgry", label:"sgry", width:125, align:"center", template:"#sgry#"},
				{id:"gpyq", label:"gpyq", width:85, align:"left", template:"#gpyq#"},
				{id:"fhdd", label:"fhdd", width:100, align:"center", template:"#fhdd#"},
				{id:"shdd", label:"shdd", width:110, align:"center", template:"#shdd#"},
				{id:"cphm", label:"cphm", width:95, align:"center", template:"#cphm#"},
				{id:"sjdh", label:"sjdh", width:115, align:"center", template:"#sjdh#"},
				{id:"qbyf", label:"qbyf", width:80, align:"right", template:"#qbyf#"}
			]
		}
	]
}

dhx.ui(config);
//loading
dhx.extend($$("mygrid"), dhx.ui.overlay);
dhx.extend($$("myform"), dhx.ui.overlay);
//render
$$("mygrid").render();

$$("myform").attachEvent("onValidationError",function(id, data){
})
$$("sgry_list").attachEvent("onitemclick",function(id, ev, trg){
	var sgry = $$("sgry").getValue();
	if (sgry.indexOf(id) < 0){
		if (sgry == ""){
			$$("sgry").setValue(id);
		}else{
			$$("sgry").setValue(sgry + "," + id);
		}
	}else{
	}
})
$$("shdd_list").attachEvent("onitemclick",function(id, ev, trg){
	var shdd = $$("shdd").getValue();
	if (shdd.indexOf(id) < 0){
		if (shdd == ""){
			$$("shdd").setValue(id);
		}else{
			$$("shdd").setValue(shdd + "," + id);
		}
	}else{
	}
})
$$("mygrid").attachEvent("onbeforeselect",function(id){
		return false;

});

$$("myform").bind($$("mygrid"));

Make sure that you pass value in correct format. It is %d.%m.%Y by default. You may change it by dateFormat property.